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Advanced Backgammon part 23B ROLLOUT

Posted By: Matt Cohn-Geier
Date: Thursday, 7 May 2009, at 12:42 a.m.

In Response To: Advanced Backgammon part 23B (Matt Cohn-Geier)

Position 224:

Blue is still well behind in the race and White has a 5 point board. Blue isn't doing badly but this is still quite a bit short of a cube.

Move number 5: Blue on roll, cube decision?

White	114
Blue	140
Position ID: drcBABa4jeHBAA Match ID: UQkAAAAAAAAA

• Blue doubles

Cube decision
Rollout cubeless equity		+0.3284
Cubeful equities:
1.	No double	+0.6417
2.	Double, pass	+1.0000	+0.3583
3.	Double, take	+0.5184	-0.1233
Proper cube action:		No redouble, take (25.6%)
Rollout details
Win W g W bg Lose L g L bg Cubeless Cubeful Player Blue owns 2-cube 0.6531 0.1192 0.0034 - 0.3469 0.0979 0.0026 +0.3284 +0.6417 Standard error 0.0029 0.0027 0.0008 - 0.0029 0.0034 0.0010 0.0073 0.0177 Player White owns 4-cube 0.6632 0.1186 0.0035 - 0.3368 0.0906 0.0030 +0.7099 +0.5184 Standard error 0.0034 0.0036 0.0008 - 0.0034 0.0031 0.0010 0.0168 0.0248
Full cubeful rollout with var.redn.
356 games, Mersenne Twister dice gen. with seed 811692981 and quasi-random dice
Play: 2-ply cubeful prune [world class]
keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
Skip pruning for 1-ply moves.
Cube: 2-ply cubeful prune [world class]

Position 225:

The spares go to good places but Blue will need to roll an 8 or higher next time. White should come out and try to get a direct shot if he rolls a 5 or 6. Playing safe is marginally correct with White's strong board.

Move number 9: Blue to play 42

White	134
Blue	76
Position ID: bNsFABxzuxkIAA Match ID: QgkKAAAAAAAA

• Blue moves 14/8

#		Ply	Move	Equity
•	1	R	14/8	+0.7266
			0.8194 0.1598 0.0036 - 0.1806 0.0087 0.0003 +0.7932 +0.7266 0.0004 0.0005 0.0001 - 0.0004 0.0002 0.0000 0.0008 0.0011
			Full cubeful rollout with var.redn.
			13521 games, Mersenne Twister dice gen. with seed 812649599 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	8/6 8/4	+0.7127 ( -0.0139)
			0.7925 0.2217 0.0071 - 0.2075 0.0108 0.0003 +0.8028 +0.7127 0.0010 0.0013 0.0003 - 0.0010 0.0003 0.0000 0.0019 0.0028
			Full cubeful rollout with var.redn.
			2366 games, Mersenne Twister dice gen. with seed 812649599 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

Position 226:

Spares on the 6 bad, spares on the 7 bad, spares on the 5 good. The 7 & 6 points will need to be cleared fairly quickly.

Move number 5: Blue to play 26

White	204
Blue	84
Position ID: yDM4AF62bScIAA Match ID: QQkZAAAAAAAA

• Blue moves 14/8 7/5

#		Ply	Move	Equity
•	1	R	14/8 7/5	+1.2129
			0.7850 0.6203 0.1334 - 0.2150 0.0012 0.0000 +1.3225 +1.2129 0.0012 0.0013 0.0013 - 0.0012 0.0001 0.0000 0.0039 0.0046
			Full cubeful rollout with var.redn.
			7900 games, Mersenne Twister dice gen. with seed 813689494 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	2	R	9/3 7/5	+1.1964 ( -0.0165)
			0.7808 0.6167 0.1321 - 0.2192 0.0022 0.0001 +1.3081 +1.1964 0.0012 0.0012 0.0012 - 0.0012 0.0001 0.0000 0.0036 0.0043
			Full cubeful rollout with var.redn.
			7898 games, Mersenne Twister dice gen. with seed 813689494 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]
	3	R	14/6	+1.1886 ( -0.0243)
			0.7796 0.6165 0.1304 - 0.2204 0.0017 0.0000 +1.3043 +1.1886 0.0018 0.0019 0.0017 - 0.0018 0.0002 0.0002 0.0057 0.0067
			Full cubeful rollout with var.redn.
			4446 games, Mersenne Twister dice gen. with seed 813689494 and quasi-random dice
			Play: 2-ply cubeful prune [world class]
			keep the first 0 0-ply moves and up to 12 more moves within equity 0.2
			Skip pruning for 1-ply moves.
			Cube: 2-ply cubeful prune [world class]

Messages In This Thread

• Advanced Backgammon part 23B
  Matt Cohn-Geier -- Monday, 4 May 2009, at 6:37 a.m.
  • Advanced Backgammon part 23B
    rory -- Monday, 4 May 2009, at 7:04 a.m.
  • Advanced Backgammon part 23B
    Christian Munk-Christensen -- Monday, 4 May 2009, at 7:50 a.m.
  • Advanced Backgammon part 23B
    misja -- Monday, 4 May 2009, at 10:52 a.m.
  • Advanced Backgammon part 23B
    Chuck Bower -- Monday, 4 May 2009, at 7:32 p.m.
  • Advanced Backgammon part 23B
    Ian Shaw -- Monday, 4 May 2009, at 10:57 p.m.
  • Advanced Backgammon part 23B
    neilkaz -- Tuesday, 5 May 2009, at 12:40 a.m.
  • Robertie's picks
    Matt Cohn-Geier -- Tuesday, 5 May 2009, at 10:12 p.m.
  • Advanced Backgammon part 23B ROLLOUT
    Matt Cohn-Geier -- Thursday, 7 May 2009, at 12:42 a.m.